VRAP Advanced Research in Virtual and Rapid Prototyping
VRAP location:Leiria date:1-5 Oct 2013
Selective laser melting (SLM) is a promising technique for the production of biometallic scaffolds for orthopaedic applications. To produce successful scaffolds, the laser parameters should be carefully selected in order to achieve open porosity especially when pores are <1000μm. In this study, we investigate the effect of different laser parameters (capable to produce dense bulk NiTi samples) on production of scaffolds with open porosities of 1000μm and varying strut thicknesses 100-300μm. Two different sets of laser parameters were used: 40W laser power with 160mm/s scanning velocity and 250W with 1000mm/s, corresponding to low and high laser parameters respectively. Micro-CT scanning experiments were carried out to illustrate the limitations of laser parameters in production of open porous scaffolds. Volume fraction and closed porosity were assessed. It was found that a large CAD mismatch was observed in the building (XZ) direction and internal porosity appears within struts of the samples produced with high laser processing parameters. The residual particles on struts were also shown to increase as strut thickness increases.